Modeling and power analysis for uplink of laser communication between airplane and satellite by CHEN Chun-yi1, YANG Hua-min1, TONG Shou-feng2, JIANG Hui-lin2

“…Finally, the minimal transmitting power, 0.873W, at transmitter was computed as link could achieve 10-7 BER.…”
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2.4 GHz CMOS Power Amplifier with Mode-Locking Structure to Enhance Gain by Changhyun Lee, Changkun Park

“…To prove the feasibility of the proposed structure, we designed a 2.4 GHz CMOS power amplifier with a 0.18 μm RFCMOS process for polar transmitter applications. The measured power added efficiency is 34.9%, while the saturated output power is 23.32 dBm. …”
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Research on BER performance of the OAM-SK FSO communication system with wavefront phase correction by Shuang LI, Ping WANG, Tao LIU, Yuting PAN, Wei WANG

“…On the basis of Gerchberg-Saxton (GS) algorithm and angular-spectrum theory, an improved wavefront phase correction algorithm to the Laguerre-Gaussian (LG) beams was proposed for the orbital angular momentum-shift keying (OAM-SK) modulation-based free space optical (FSO) communication system under weak atmospheric turbulence.The light field distributions of the probe beam at transmitter and receiver were regarded as the input of the improved wavefront phase correction algorithm.And the correction phase mask was iteratively calculated to correct the distorted LG beams, thereby alleviating the inter-model crosstalk caused by atmospheric turbulence.Simulation results show that the improved wavefront phase correction algorithm is superior to the conditional GS algorithm.And with the increase of the refractive-index structure parameter, the bit error rate (BER) performance of the OAM-SK FSO communication system is significantly improved.…”
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Cross-Layer Framework for Multiuser Real Time H.264/AVC Video Encoding and Transmission over Block Fading MIMO Channels Using Outage Probability by Slavche Pejoski, Venceslav Kafedziski

“…We show the effectiveness of the proposed framework for video transmission over Rayleigh MIMO block fading channels, when channel distribution information is available at the transmitter.…”
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Wideband DBF phased array antenna on LEO satellite by LIANG Guang1, GONG Wen-bin1, LIU Hui-jie1, YU Jin-pei1

“…Ultimately a 61-channel phased array transmitter antenna with 16 simultaneous beams was designed. …”
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A genetic algorithm based method of optimizing dispersion matrix for RDSM system by Peng ZHANG, Xiaoping JIN, Dongxiao CHEN

“…Rectangular differential spatial modulation (RDSM) is a multi-antenna incoherent modulation technology with high spectral efficiency, low power consumption, and zero-overhead for channel estimation.RDSM is especially suitable for 6G communication systems, such as fast-moving Internet of vehicles, Internet of things, cellular networks, etc.However, the construction of the sparse rectangular unitary space-time dispersion matrix (DM) at transmitter is a problem.The proposed Genetic algorithm (GA) will result in less computational complexity than the currently used random research.The fitness of GA was calculated by the rank and determinant criterion (RDC) method to avoid discussions in differential system.Due to characteristics of constellation symbols of RDSM, the proposed method reduced the computational complexity during each single iteration in GA.The simulation results show that the optimized DMS can significantly improve the bit error rate (BER) performance of the RDSM system.Compared with random search, the low-complexity GA effectively improves the DMS optimization efficiency of RDSM.The computational complexity required for optimizing DMS is about 0.1% of random search optimization method.…”
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Suppression of co-channel interference in NGSO constellation system with interference alignment by Bing DU, Jiawang LI, Xianmei WANG, Wei LI, Xiangnan LIU, Haijun ZHANG

“…Aiming at the problem that in the current space， non-geostationary satellite orbit （NGSO） constellation systems were increasing day by day， there are more and more satellite networks nearby orbiting using the same frequency band， and the problem of co-channel interference between NGSO constellation systems and between NGSO constellation systems and traditional geostationary satellite orbit （GSO） constellation systems had become increasingly serious， the interference alignment algorithms of wireless communication was proposed， which matches the precoding matrix of the characteristic channel at the transmitter according to the transmission channel information of the satellite network to alleviate the co-channel interference problem of the low-orbit satellite network.The ChinaSat， OneWeb and Fortran systems were used to simulate and compare the interference values before and after using the interference alignment algorithms， which proves the feasibility of the proposed method and provides a reference for future research on such problems.…”
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Design of beamforming for IRS multi-partition-aided THz multi-subarray by Zufan ZHANG, Rui TANG

“…In the IRS-aided THz communication system, in order to break the channel sparsity limitation on the system spatial multiplexing gain, a hybrid beam forming architecture with wide-spaced multi-subarrays at the transceiver/transmitter side was proposed and the transmission scheme of IRS multi-partition-aided THz multi-subarrays was designed.Firstly, a non-convex objective function with multivariate coupling and non-convex constraints was constructed based on the principle of maximizing spectrum efficiency.Then, the optimization problem was decoupled into two easy-to-solve sub-problems, namely, the reflection coefficient matrix design of IRS and the hybrid beamforming matrix design at the transceiver/receiver.Finally, the Riemannian manifold optimization algorithm was used to calculate the reflection coefficient matrix of IRS, and the closed solution of the hybrid beamforming matrix design at the transceiver/receiver was obtained through mathematical derivation.Simulation results show that compared with the baseline scheme, the proposed scheme can achieve better spectrum efficiency.…”
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Energy Efficiency Maximization with Optimal Beamforming in Secure MISO CRNs with SWIPT by Liang Xue, Yao Ma, Miao Zhang, Wanqiang Qin, Jin-Long Wang, Yazhou Wu

“…When the instantaneous channel state information (CSI) of the eavesdropping link is unknown to the legitimate transmitter, another interruption-constrained energy efficiency optimization problem is proposed and the Bernstein-type inequality (BTI) is used to conservatively approximate the probability constraint. …”
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Performance Prediction of a Synchronization Link for Distributed Aerospace Wireless Systems by Wen-Qin Wang, Huaizong Shao

“…In a distributed aerospace wireless system, since the transmitter and receiver placed on separated platforms which use independent master oscillators, there is no cancellation of low-frequency phase noise as in the monostatic cases. …”
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Performance analysis of orthogonal signals with TASP/MRC diversity by Guangqiu LI, Siting WANG

“…In order to solve the design problem of predictive transmit antenna selection (TASP) / receive antenna maximum ratio combining (MRC) wireless communication system with the minimum mean square error (MMSE) channel prediction,exact and approximate closed-forms for the average symbol error rate (ASER) of M-ary ortho-gonal and biorthogonal signals with coherent detection and TASP/MRC over Rayleigh block fading channel were de-rived by using parabolic cylinder function,the approximate expression of Gaussian Q-function and moment generat-ing function (MGF) based analysis approach respectively.Numerical and simulation results show that the theoretical analysis of the ASERs of orthogonal and biorthogonal signals is exact and the approximate closed-form for the ASER of orthogonal signals is accurate.The above exact or/and approximate closed-forms of ASER of orthogonal and biortho-gonal signals with coherent detection and TASP/MRC can be used to determine the number of antennas of transmitter and receiver and the parameters of predictor quickly,instead of the time-consuming and inefficient computer simulation.…”
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DMA-based key generation method for IoT scenario by Yinuo HAO, Zhou ZHONG, Xiaoli SUN, Liang JIN

“…Aiming at the problems of slow update frequency of channel key, low generation rate and limited node resources in the IoT scenario, a DMA-based physical layer key generation method was proposed, by using the agility and reconfigurability of DMA to improve the time variability and randomness of received signal.Firstly, DMA was used by the transmitter to randomly weight the signal and send it to the receiver, which could enhance the randomness of signals on the premise of ensuring the transparent reception of the signal.Then, the key from the received signal was extracted by the sender and receiver.By combining the rapid changeability and randomness of DMA, the randomness of signal source and the randomness of natural channel, a composite channel was constructed to improve the randomness of the key source.In addition, the channel estimation was transfered overhead from the terminal to the base station, which effectively reduced the overhead and delay of the communication system, and was suitable for IoT scenarios with asymmetric resources and lightweight equipment.Simulation results show that the proposed method can effectively improve the key generation rate in quasi-static scenarios, and the generated physical layer key has passed the NIST test.…”
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A massive MIMO-OTFS robust transmission scheme for vehicular networks using sensing-assisted communication by Weidong WANG, Hui GAO, Xin SU, Limin XIAO, Shiqiang SUO, Qiusha GONG

“…For a multi-user integrated sensing and communication system in the network of vehicles, a robust sensing-assisted communication massive multiple-input multiple-output (MIMO) orthogonal time frequency space (OTFS) transmission scheme was proposed.Due to the limited sensing accuracy of the radar, errors existed in the channel state information (CSI) reconstructed based on sensing parameters.The transmission performance decreased as a result.To address this issue, the CSI in the delay doppler domain was reconstructed based on the sensing parameters by the transmitter firstly.And a robust beam forming scheme was designed considering the CSI error.Secondly, the channel estimation error and inter user interference were perceived by receivers based on sensing parameters.Then the robust receiver was designed by incorporating the perceived interference errors into the signal detector in an analytical way.Finally, numerical simulation results show that the proposed method effectively reduces the system bit error rate and increases the data reception rate of users.The proposed method improves the overall system performance in this situation.…”
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Design of Four-Plate Parallel Dynamic Capacitive Wireless Power Transfer Coupler for Mobile Robot Wireless-Charging Applications by Hongguk Bae, Sangwook Park

“…Additionally, a null-power point characteristic, where efficiency sharply decreases when the receiver moves outside the transmitter’s range, was observed. The detailed theoretical design of the practical equivalent circuit for electric resonance-based dynamic WPT couplers is expected to contribute to the design of couplers for various specifications in future applications.…”
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Hybrid precoding with sub-connected architecture for millimeter wave massive MIMO system by Haiyan CAO, Xiaohui YANG, Wenjuan HU, Zichang MA, Fangmin XU, Xin FANG

“…A hybrid precoding scheme in the millimeter wave massive MIMO system was proposed with sub-connected architecture at the transmitter and digital combining at the receiver.In this scheme,the digital precoder and combiner were designed based on the singular value decomposition (SVD) of the equivalent channel matrix,while the optimal analog precoder was obtained by blocking the equivalent channel to maximize spectral efficiency according to the block diagonalization.Considering the hardware cost and power consumption,the precoding scheme with sub-connected architecture at the receiver was further proposed.Otherwise,the analog precoder and combiner were iteratively updated.Simulation results show that the proposed scheme which focuses on the digital combining at the receiver has better performance than successive interference cancelation (SIC)-based hybrid precoding.In addition,though the proposed scheme which focuses on the hybrid combining with sub-connected architecture at the receiver has worse performance than SIC-based hybrid precoding,the power consumption and hardware cost are greatly reduced.…”
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Opportunistic secure transmission scheme for simultaneous wireless information and power transfer by Keming MA, Yajun CHEN, Xin HU, Kaizhi HUANG, Xinsheng JI

“…Aiming at the different requirements of energy transmission and information transmission in simultaneous wireless information and power transfer (SWIPT),an opportunistic transmission scheme was proposed for enhancing physical layer security.Firstly,a SWIPT network with multi-cells was considered where multi-users,multi-eavesdroppers and the users were assumed to adopt time-switching based receivers and employ non-linear conversion model to harvest energy.The transmitter could dynamically switch between information transmission and power transfer according to the channel state,breaking the traditional fixed slot allocation scheme of energy transmission and information transmission.On this basis,the performances of energy transmission and information transmission were analyzed comprehensively,including the stability and efficiency of energy transmission,and the reliability and security of information transmission in the scenario of independent eavesdropping and joint eavesdropping.Next,a switching threshold optimization model was given to maximize its secrecy throughput under the constraint of the energy transmission,the reliability and secrecy performance requirements of information transmission.Finally,simulation results verify the validity of the proposed scheme.…”
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Vibration Suppression Method of a Hydraulic Flexible Manipulator based on the System of Piezoelectric Feedback Driven by Luo Tianhong, Miao Changbin, Xu Xiangyang, Ma Xiangyu, Li Fuying

“…In order to suppress the vibration in the end of large double-link hydraulic flexible manipulator,taking the heavy load hydraulic flexible mechanical arm as the study object and aiming at the end of arm movement in the process of vibration phenomenon,by the servo-hydraulic system-Euler Bernoulli model,Lagrange equation and Jacobian matrix,a piezoelectric feedback driven system control method is designed,through the end of the robot arm equipped with sensitive piezoelectric transmitter,piezoelectric actuators and inversion control design methods,the movement of servo hydraulic cylinder vibration,the hydraulic cylinder with manipulator friction and manipulator rod elastic vibration influence of the hydraulic flexible manipulator end vibration are studied. …”
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Power Management in Multiuser Adaptive Modulation Transmission under QoS Requirements by Saud Althunibat, Nizar Zorba, Charalabos Skianis, Christos Verikoukis

“…A transmitter power management mechanism is presented in this paper where Multiple-Input Multiple-Output (MIMO) Multiuser Random Beamforming with Adaptive Modulation strategy is performed by the system. …”
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High spectral efficiency SSB-PAM-DD scheme with high linewidth tolerance by Dongxu LU, Xian ZHOU, Fei LIU, Jiahao HUO, Jinhui YUAN, Keping LONG

“…For low-cost and high chromatic dispersion (CD) robustness single sideband (SSB) with direct detection (DD), three schemes of SSB with pulse amplitude modulation (PAM) were investigated.Among that, the highest spectral efficiency was achieved by the scheme of adding the frequency down-conversion at the transmitter.However, that scheme reduces the tolerance for laser linewidth.Hence, based on the character of the SSB-PAM signal, a DSP scheme was proposed, including a modified equalization algorithm with phase distortion immunity and blind phase search algorithm.The simulation results show that the modified scheme can tolerate 1 MHz linewidth for 112 Gbit/s SSB-PAM-DD, while the original scheme for SSB-PAM was only 100 kHz at the same bit error rate (BER) threshold.Therefore, the proposed scheme can achieve a high frequency efficiency, high linewidth tolerance, and low-cost SSB-PAM signaling transmission.…”
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Physical layer security of MIMO wireless systems with adaptive modulation by Hui LI, Guangqiu LI, Yancui LUO, Huizhi LIU

“…To solve the problems of low spectral efficiency and poor performance of physical layer security (PLS) in single-input single-output (SISO) wireless systems with adaptive modulation in the presence of an active eavesdropper, multiple-input multiple-output (MIMO) wireless systems with secure adaptive modulation (SAM) were proposed.The design idea was to improve the spectral efficiency of the main channel by antenna diversity technology, which used the transmit antenna selection (TAS) at the transmitter and the maximal ratio combining (MRC) at the legitimate receiver to improve the signal-to-noise ratio.Simultaneously, the PLS of the legitimate receiver was guaranteed by limiting the bit error rate of the active eavesdropper so that it could not demodulate the confidential information from the main channel.With the joint constraints of the average transmission power and PLS, the optimal switching thresholds and the analytical expressions of spectral efficiency and the eavesdropper’s average bit error rate of the SAM-MIMO systems were derived.Numerical and simulation results show that SAM systems using TAS/MRC technology can not only improve the spectral efficiency of the main channel, but also ensure the PLS against the active eavesdropper, compared with the SAM-SISO systems.…”
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